The present invention is directed to the production of non-skid or slip-resistant material and more particularly to a method of producing a slip-resistant substrate by depositing or cladding raised, bead-like configurations of a compatible or dissimilar materials at select locations on the substrate surface by using a high power radiant energy source, such as a laser, an electron beam, plasma transfer arc and the like, and a substrate including the same thereon.
In certain industrial settings there are many locations that are difficult or even hazardous for personnel and/or motorized vehicles to move across due to materials that may coat the floor. Such materials include water, mud, snow, oil, blood, inks, and other slippery chemicals. If no precautions are taken, slips and falls may occur to personnel that can lead to costly injuries.
In order to reduce the chances of slips and falls, many propose to alter the surfaces to increase traction (or the coefficient of friction) in areas where accidents are most likely to occur. There are a number of methods to alter the surface characteristics to increase the traction. They include using stamped or rolled materials, flame sprayed aluminum coatings, hot rolled materials, and grit bearing paints or tapes. All of these materials increase traction by populating the surface with aspirates which increase the frictional forces.
However, the presently available non-skid materials all have some negative aspects. Rolled materials, such as Diamond Plate, do not increase the frictional forces substantially because of the large size of the features that are rolled into the material. Stamped materials, materials that are cut and bent, have very high frictional forces but must be formed out of thin materials which cannot withstand high loadings (such as with motorized material handlers) and must be formed and joined to the area that is covered. Flame sprayed aluminum, paints, and tapes often flake or wear-off, especially under high loads. The use of hot rolled fabricated (carbon steel) materials is limited since they cannot be formed extensively.
Further, as noted above, conventional methods for making non-skid materials include hot-rolling of particles into a surface, hot-rolling of "rough" patterns into the surface, and flame-spraying of a material onto the surface, such as aluminum. The rolling of particles or patterns for producing the non-skid effect requires that the final structure be cut from a large plate. If the plate requires further fabrication, however, such as bending, cutting, and/or shaping, it may result in a loss of the non-skid characteristics of the plate. Moreover, the rolling of particles and flame-spraying techniques do not result in true metallurgical bonding between the "roughing" agent (the particles) and the base material. Therefore, this may lead to defoliation of the particles which can then become trapped in the machinery and adversely affect the non-skid characteristics of the material.
The use of laser or other high energy carrying radiation beams in metallic coating of a metallic substrate for repairing or improving wear resistance, or surface hardening of a metallic article is disclosed in U.S. Pat. Nos. 4,251,709; 4,281,030; 4,299,860; 4,300,474; 4,488,882; 4,698,237; 4,743,733; 4,810,525; German Patent 2,129,926; and Bruck, G. J., "High Power Laser Beam Cladding", R&D Paper 87-1D4-METAL-P1, Westinghouse (Jan. 30, 1987) and Nurminen et al., "Laser Cladding and Alloying For Surface Modifications", R&D Scientific Paper 87-1D4-METAL-P2, Westinghouse (Aug. 10, 1987).
The conventional techniques appear to emphasize, however, smooth coating of substrates, and therefore, cannot be used in fabricating non-skid or slip resistant surfaces of plates, equipment, fixtures, or structures, for application in hazardous areas for personnel protection. The need for such slip-resistant or non-skid surfaces is particularly evident on, for example, the deck plate or launching pad of a naval vessel, such as an aircraft carrier. Due to the adverse and, at times, hostile conditions that are frequently encountered by naval personnel, it becomes critical that the deck surface have a high coefficient of friction to avoid slipping, skidding, etc.
Accordingly, there is a need in the art for a method of producing a slip-resistant material which does not suffer from the disadvantages associated with conventional techniques, and a novel substrate material including improved slip-resistant characteristics.